Below is a brief guide from Mumoto as follows:
This is what I did to get it to work:
Install latest multiMAN
Install Blackb0x FTP Server
Launch Blackb0x FTP Server (After configurating networkcard)
Use Filezilla to transfer files from PC -> PS3 (Eboot Patch included)
Inserted random Game-DVD
Opened Multiman, clicked FIFA 13 and in XMB clicked FIFA 13 again
Play